/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.spark.storage

import java.nio.ByteBuffer


/**
 * An interface for providing data for blocks.
 *
 * getBlockData returns either a FileSegment (for zero-copy send), or a ByteBuffer.
 *
 * Aside from unit tests, [[BlockManager]] is the main class that implements this.
 */
private[spark] trait BlockDataProvider {
  def getBlockData(blockId: String): Either[FileSegment, ByteBuffer]
}
